The invention relates to a power converter for a computer device and to a method for operating a power converter for a computer device. Further, the invention relates to method and to a computer program for operating a power converter for a computer device.
Conventional computer devices, like processors, operate on even lower supply voltages, resulting in higher supply currents for the same dissipating power. For example, there are processors that require up to 145 A or more at typically 1V supply voltage. With such a high current, even short traces on a printed circuit board with a resistance in the milliohm range may cause a considerable voltage drop, in particular considering the low supply voltage of 1V for example. In order to guarantee a correct voltage at the load device, a separate feedback wire may be used that senses the resulting voltage as close to the load as possible for example on the processor die directly. Disadvantageously, such as separate feedback wire may be not used in cases where it is hard or even impossible to install such a feedback wire, for example because of limited available space in the processing system.
Document U.S. Pat. No. 6,737,840 B2 shows a switching DC/DC converter with the output voltage changing inversely to any change in the converter inductor current. In the DC-DC converter, a technique for sensing current supplied to a load and establishing an output voltage that conforms to a predetermined load line is used. The current carried by an inductor is sensed and used to control the duty cycle of the voltage applied to the inductor, thereby controlling the output voltage. A current sensing circuit includes a feedback network. A pole attributable to the feedback network cancels a zero attributable to the inductor so that a control voltage is developed that varies substantially linearly with the load current.
Document U.S. Pat. No. 7,370,213 B2 describes a power supply unit and a computer. A series power supply circuit and a switching power supply circuit are combined within a single power supply unit. The switching power supply circuit provides an efficiency lower than that of the series power supply circuit under a light load and provides efficiency higher than that of the series power supply circuit under a heavy load. A standby signal that is asserted under a light load and is deasserted under a heavy load is input to a negative logic enable terminal of the series power supply circuit through an inverter0. The standby signal is directly input to the negative logic enable terminal of a PWM controller in the switching power supply circuit. A series power supply circuit and a switching power supply circuit are combined within a single power supply unit. The switching power supply circuit provides an efficiency lower than that of the series power supply circuit under a light load and provides efficiency higher than that of the series power supply circuit under a heavy load. A standby signal that is asserted under a light load and is deasserted under a heavy load is input to a negative logic enable terminal of the series power supply circuit through an inverter0. The standby signal is directly input to the negative logic enable terminal of a PWM controller in the switching power supply circuit.
Document U.S. Pat. No. 8,120,346 B2 shows a method and an apparatus for current sensing the current in a circuit, such as an inductor circuit. The current sensing system may comprise an RC element connected such that the RC time constant matches the L/R time constant of the inductor. The current sensor may be configured to generate voltages that are proportional to the instantaneous current in the inductor with scaled gain for a wide range of inductor self-resistance values.
Document U.S. Pat. No. 6,424,129 B1 describes a method and an apparatus for accurately sensing an output current in a DC-to-DC voltage converter. The apparatus and the method for accurately sensing the output current delivered to a load by a buck-type DC-to-DC switched mode power converter corrects for thermal variation of the output inductor. A first current sense signal provides a fast indication of output current of the DC-to-DC converter that is susceptible to thermal variation of the output inductor of the converter, and a second current sense signal provides a slow but accurate indication of output current that is not affected by the thermal variation. The first current sense signal is corrected using the second current sense signal to yield accurate output current sensing information.
Document U.S. Pat. No. 7,268,527 B2 shows a method and an apparatus for determining a load current in a CPU core voltage regulator. The apparatus and the method for measuring output current and power in real-time is provided for a CPU core powered by a DC-to-DC power converter having active voltage positioning. A switched mode power converter may comprise at least one power switch operatively coupled to an input voltage source, an output filter operatively coupled to the at least one power switch to provide an output voltage and output current to a load, and a control circuit coupled to the at least one power switch. The control circuit activates the power switch with a duty cycle controlled to regulate at least one of the output voltage and the output current. The control circuit receives a first control signal defining a desired value for the output voltage, a second control signal defining a relationship between voltage input and current draw for the load, and a voltage sense signal corresponding to an actual value of the output voltage. The control circuit thereby provides a measurement of load current.
Document US 2012/0154013 A1 describes an apparatus including a memory module and power converter and method of operating the same. The apparatus includes a memory module, located on a circuit board, configured to operate from a first voltage and a second voltage being a multiple of the first voltage. The apparatus also includes a power converter employing a switched-capacitor power train, located on the circuit board, configured to provide the second voltage for the memory module from the first voltage.
Accordingly, it is an aspect of the present invention to provide an improved power converter for a computer device.